"Reduce size without losing quality" is slightly a myth — some trade is always involved — but you can get very close by pulling the right levers in the right order. Here is how to shrink an image so the loss is invisible.
1. Resize the dimensions first
This is the biggest, most overlooked win. A photo displayed at 800 pixels wide does not need to be 4000 pixels wide. Halving the width and height cuts the pixel count to a quarter — a huge size reduction with zero visible loss at the display size. Use the image resizer to set sensible dimensions before anything else.
2. Pick the right format
Format matters enormously. Photographs belong in JPG or WebP, never PNG — a photo saved as PNG can be many times larger. Graphics, logos and screenshots belong in PNG (or WebP). If the destination is a modern website, WebP is typically 25–35% smaller than JPG at the same quality.
3. Compress to a sensible quality
JPG and WebP let you trade quality for size. The trick is that the last 10% of quality costs most of the file size while being nearly invisible — so a 100% export is wasteful. A tool that targets an exact size does this automatically: it finds the highest quality that still fits your target, so you never over- or under-compress.
4. Strip metadata
Photos carry hidden EXIF data — GPS, camera settings, thumbnails — that adds weight and leaks privacy. Removing it shaves a little size and is worth doing before sharing regardless.
Putting it together
The reliable recipe: resize to the dimensions you actually need → choose JPG or WebP → compress to a target size. Do those three and a multi-megabyte photo becomes a lean file that still looks sharp. Everything here runs in your browser, so your images stay private throughout.
Dimensions are usually the biggest lever
People reach for quality sliders first, but dimensions almost always matter more. A modern phone photo can be four thousand pixels across. Displayed on a web page at eight hundred pixels wide, or attached to a form that will be printed on a quarter of a page, three quarters of those pixels are never seen and are pure weight. Halving the width and height quarters the pixel count, and the file usually shrinks by something close to the same proportion with no visible difference at the size it will actually be viewed. Start there with the image resizer before touching anything else.
Match the format to the picture
Format choice can be worth more than any amount of careful compression. Photographs belong in JPG or WebP, which are built for the gradual tonal changes in a real scene. Screenshots, logos, diagrams and anything with text or flat colour belong in PNG or WebP, which handle hard edges without the smearing JPG introduces around them. The classic mistake is saving a photograph as PNG, which can easily produce a file five or ten times larger than necessary, and the opposite mistake is saving a screenshot of text as a heavily compressed JPG, which makes the text look fuzzy.
What quality settings actually do
Lowering JPG quality discards fine detail, and the losses accumulate in the places your eye is drawn to: the edges of text, the border between a subject and the background, and areas of even colour where faint blocky patterns start to appear. Between roughly eighty and ninety per cent quality, most people cannot tell the difference from the original. Below about sixty the damage becomes visible. This is why guessing with a slider is inefficient: you either stop too early and miss the limit, or overshoot and ruin the picture.
Compress once, not repeatedly
JPG compression is lossy and not reversible. Each time a JPG is opened, edited and saved again, it is re-compressed and a little more detail is thrown away for good. Re-saving the same file five times leaves it noticeably worse even if the quality setting never changed. Always work from the original where you can, make your changes, and save once at the end rather than iterating on an already compressed copy.
Working to an exact limit
When a form specifies a number, aiming at it by hand wastes time. The image compressor searches for the highest quality that still fits the target you give it and, if quality alone is not enough, reduces the dimensions as well. Common limits have their own pages, such as 100KB, 50KB and 20KB. One useful habit: do not compress further than the limit requires. If the form says two hundred kilobytes, aim at two hundred rather than fifty, because every kilobyte you give up below the limit is quality you threw away for nothing.